Patrik Kania

Detailed study of fine and hyperfine structures in rotational spectra of the free fluoroformyloxyl radical FCO2

More than 160 new hyperfine components of rotational transitions of the free fluoroformyloxyl radical FCO(2) have been measured using the Prague millimeter wave high resolution spectrometer. The frequencies of these transitions together with the previously measured data were analyzed in detail and precise values of magnetic hyperfine and fine parameters were obtained. These new parameters significantly improve the values of previously determined hyperfine parameters which were rather unreliable. The new fine and hyperfine parameters obtained in this study are compatible with those of the simultaneously electron paramagnetic resonance study. Besides that, significantly improved ground state rotational and centrifugal distortion constants of the fluoroformyloxyl radical were derived.

The fluoroformyloxyl radical geometry and ground-state rotational spectra of the free FC18O2· radical.

The rotational spectra of the isotopically substituted free fluoroformyloxyl radical FC(18)O(2·) were measured using the Prague millimeter-wave high-resolution spectrometer. More than 110 rotational-fine-hyperfine transition lines were observed and assigned to appropriate quantum numbers in the frequency range of 235-270 GHz. The obtained transition frequencies were analyzed with standard effective Hamiltonians to acquire a set of precise rotational, centrifugal-distortion, fine, and hyperfine structure molecular constants. Merging the new FC(18)O(2·) isotopologue molecular parameters with those previously obtained for the ordinary FC(16)O(2)[middle dot] radical, the substitution molecular geometry in the ground vibronic state was evaluated. The molecular parameters for both radical isotopologues were also calculated by several quantum chemistry methods and their calculated mutual ratios are in remarkable agreement with the experimental FC(16)O(2·)/FC(18)O(2·) parameter ratios. The measurements, assignments of the 18-oxygen isotopologue FC(18)O(2·) radical millimeter-wave transitions, as well as the derivation of the fluoroformyloxyl radical ground-state geometry have been carried out for the first time.

Geometry and Microwave Rotational Spectrum of the FC16O18O• Radical

The rotational spectrum of an asymmetrically substituted isotopologue of the fluoroformyloxyl radical FC(16)O(18)O(•) with resolved fine and hyperfine structures were measured and analyzed for the very first time. The molecular parameters of this radical obtained from the spectral analysis were processed along with the symmetrical isotopologues FC(16)O2(•) and FC(18)O2(•) and accurate substitution geometry was attained. In addition to those, coupled cluster quantum chemistry calculations were used to scale the experimental parameters, and in this manner, trustworthy values of the equilibrium and ground state geometries were derived.

Microwave spectra of fluoroformyloxyl and fluorosulfate radicals

Rotational spectra of fluoroformyloxyl (FCO2ldr) and fluorosulfate (FSO3ldr) molecular free radicals were measured in millimetre wave region and analyzed in detail using matrix elements of rotational, centrifugal distortion, fine and hyperfine effective Hamiltonian terms. The microwave spectra of the FSO3ldr free radical were observed, identified and analyzed for the first time.